Week-by-week guide to pregnancy

happy couple looking at pregnancy test results
When you're pregnant, you have lots of questions. Our week-by-week pregnancy guide is packed with lots of useful information. From what's happening inside your body, to how your baby is developing, and tips and advice on having a healthy pregnancy – this is your one-stop pregnancy guide!

First trimester

Our week-by-week pregnancy guide is full of essential information. From early pregnancy symptoms to how your baby is growing and developing, you' ll find it all here. Happy reading!

Week 5 – your first trimester

To the outside world, you'll look much the same as usual – there's no tell-tale bump to give the game away. But inside, extraordinary things are happening.

What's happening in my body?

Your baby's nervous system is developing, and the brain and spinal cord are taking shape. The tiny heart is starting to form and will beat for the first time around now.

Many women realise that they're pregnant around week 5. You might notice that your period's late, you may feel a bit under the weather and think "Hmmm, am I pregnant?" Your suspicions could be confirmed by a home pregnancy test (these are up to 99% accurate). If you're wondering when to take a pregnancy test, then now's a good time, as they're sensitive to changes in your urine from week 3 or 4 onwards.

Finding out you're pregnant can be really exciting, but it's very normal to have worries too. More than 1 in 10 mums feel anxious during pregnancy. It's easy to get things out of proportion, as you could feel physically and emotionally exhausted, because of all the pregnancy hormones zipping around your body. Don't bottle things up – talk to your midwife or doctor. If you're feeling stressed, try relaxing breathing exercises. Look after yourself this week, because you and your baby deserve it!

Anyone for gherkins and custard?

Are you getting cravings? Some women do, some don't. Pregnancy cravings are caused by hormonal changes affecting your senses of taste and smell. Some mums go off coffee and curries. Others crave cake or fruit. Try eating a balanced healthy diet. If you get any weird pregnancy cravings, like wanting to eat dirt, talk to your midwife or doctor, as you may have a dangerous condition called pica caused by a lack of iron.

Early pregnancy symptoms (at 5 weeks)

If you've taken a test and know that you're pregnant, then congratulations! It's still early days, and many women won't know they're pregnant at 5 weeks. We don't all have menstrual cycles that work like clockwork, so many women won't realise their period is late. They might see spotting, and think that's their period, it can also be a sign of an embryo burying into the womb (implantation bleeding).

Other mums-to-be will really start to feel the impact of the pregnancy hormone, human chorionic gonadotropin. In the first trimester, which is up until week 12, many women feel extreme tiredness. Other early signs of pregnancy, which are the same as those in week 4, can include:

  • a metallic taste in your mouth
  • sore breasts
  • nausea (also known as 'morning sickness', though it can strike at any time)
  • mood swings
  • new likes and dislikes – anyone for a slice of orange with pickle? Read our advice on weird pregnancy cravings
  • a heightened sense of smell
  • needing to wee more frequently
  • a milky white pregnancy discharge from your vagina
  • light spotting (see your doctor if you get bleeding in pregnancy)
  • cramping, a bit like period pains
  • darkened skin on your face or brown patches – this is known as chloasma faciei or the "mask of pregnancy"
  • thicker and shinier hair
  • bloating and the feeling of being bloated

There's more too! Tommy's, the baby charity, has a list of 10 common pregnancy complaints with advice on how to manage them.

If you don't have any early pregnancy symptoms, then you're probably just lucky! However if you do feel anxious about anything then use the support that's available from your midwife or doctor.

What does my baby look like?

Your baby, or embryo, is around 2mm long (about the size of a sesame seed). The face is starting to take shape, with a tiny, weeny nose and little eyes which will stay shut until around 28 weeks. The baby's brain and spinal cord are forming rapidly inside you.

The baby-to-be already has some of its own blood vessels and a string of them will make up the umbilical cord. This cord will deliver the growing bundle of cells with everything it needs from the placenta. The placenta, which is being created now, will give your baby nutrients and oxygen, while removing waste products. It's basically like a store-cupboard and toilet, rolled into one!

Action stations

The advice for week 5 is the same as for week 4 - basically keep up the good work looking after yourself!

In particular…

Share the news with your GP or ask for an appointment with a midwife at your doctors' surgery. Alternatively you can refer yourself to your local hospital – look for contact details on their website.

You'll need to arrange a 'booking appointment'. This usually takes place between weeks 8 and 12 and takes around an hour. You can talk about the options for your pregnancy and the birth. Plus you'll be offered screening tests for infectious diseases, and conditions such as Down's syndrome. You could ask about the Maternity Transformation Programme and how it could benefit you.

You will be offered your first dating scan at 8 to 14 weeks. This is a highlight for many women.

In total, most first time mums will have around 10 appointments and two scans. Ask if it's possible to see the same carer for your entire pregnancy, to give you continuity.

Ask your midwife or doctor about online antenatal classes – they may be able to recommend one. The charity Tommy's has lots of useful information on antenatal classes and preparing you for birth.

It's early days, but ask your partner if they would like to take part in the antenatal classes. These classes will give you the chance to meet other people and prepare you for parenthood. The NCT offers online antenatal classes with small groups of people that live locally to you.

Do your best to stop smoking, give up alcohol and go easy on the cappuccinos. We know that's easy to say, but hard to do. Ask your midwife or GP for support.

Take prenatal vitamins. You're advised to take 400 micrograms of folic acid, every day, until at least week 12. This helps your baby's nervous system to form and offers some protection from conditions such as spina bifida.

We can usually get enough vitamin D from sunlight, but as we are at home a lot more at the moment, you may not be getting enough. If you're pregnant, or breastfeeding, you should consider taking a daily vitamin D supplement. It's worth checking if you're entitled to free vitamins.

Do you think you or your partner could have a sexually transmitted infection (STI)? If so, get it checked out, as this could affect your baby's development. Talk to your midwife or GP, or visit a sexual health clinic.

Get moving! It's recommended that pregnant women do 150 minutes of exercise throughout the week. You could start off with just 10 minutes of daily exercise - perhaps take a brisk walk outside. Check out Sport England's #StayInWorkOut online exercises (scroll to the pregnancy section). Listen to your body and do what feels right for you.

Don't eat for two! That's a big myth. If you pile on the pounds, you could put you and your baby at risk of health problems such as high blood pressure. Eat healthily, with plenty of fresh fruit and veg, and avoid processed, fatty and salty foods. You may be able to get free milk, fruit and veg through the Healthy Start scheme.

If you have a longterm health condition, then let your specialist or GP know that you're pregnant as soon as possible. Don't stop taking any regular medication without discussing it first with your doctor.

How are you today? If you're feeling anxious or low, then talk to your midwife or doctor who can point you in the right direction to get all the support that you need. You could also discuss your worries with your partner, friends and family. You may be worried about your relationship, or money, or having somewhere permanent to live. Don't bottle it up – you're important, so ask for help if you need it!

This week's treat

Enjoy some 'me' time for your mental health. How about hosting a film night? Enjoy healthy snacks, such as freshly made plain popcorn, or carrots and hummus.

Go back to week 4

Go to week 6

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